Motor driven syringe



-J. J. RODRIGUES July 2s, 1959 l MOTOR DRIVEN SYRINGE Filed April 16, 1957 2 Sheets-Sheet 1 A TTORNEV July 28, 1,959 J. J. RODRIGUES 2,896,621

MOTOR DRIVEN SYRINGE Filed April 16, 1957 2 Sheets-Sheet 2 BY @MM A T TO/PNEV United States Patent MOTOR DRIVEN SYRINGE John J. Rodrigues, Berkeley, Calif.

Application April 16, 1957, Serial No. 653,230

Claims. (Cl. 12S-218) This invention relates to motor driven syringes.

It is an object of this invention to provide a motor driven syringe which delivers fluid more. accurately and more uniformly than `the capability of existing motor driven syringes.

Another object of this invention is to provide a motor driven syringe in which the plunger of the syringe is actuated directly by a motor driven cam.

A further object of this invention is to provide a motor driven syringe in which the syringe is supported rigidly without subjecting the barrel of the syringe to pressures tending to `distort the barrel and interfering with the accurate and uniform operation of the syringe.

'Still another object of the invention is to provide a syringe mounted for versatility for a plurality of different operations.

The foregoing and` other objects of the invention will `become apparent upon an understanding of the following specification when considered in the light of the accompanying drawings and the appended claims.

Inthe drawings:

Fig. 1 is a front elevation of a selected embodiment of my invention;

Fig. 2 is a top plan view of the device illustrated in Fig. 1;

Fig. 3 is a cross-section view taken along the line 3 3 in Fig. l;

Fig. 4 is a ydetail view of a cam acting as a switch actuator plate used in the device illustrated in Figures l to 3;

Fig. 5 is a front View of another selected embodiment of my invention; t

Fig. 6 is a top plan view of the device illustrated in Fig. 5; and

Fig. 7 is a side view of the device illustrated in Figs. 5 and 6.

The selected embodiment of the apparatus illustrated in Figs. 1-4 is used in conjunction with 'an ordinary hypodermic syringe 1. `Such a syringe consists of a cylindricalbarrel 2 with a lip 3 and nozzle 4 thereon; a plunger 5 with a head I6 thereon and a needle assembly 7 attached to nozzle 4.

As illustrated, a metal bracket 8 acts as a frame for the several elements of the device. Bracket 8 has a front face 9, rear face 10, top edge 11 and bottom edge 12. Two longitudinally extending elongated slots 13, 14 are `provided in bracket 8. Slot 13 is positioned to one side of the vertical center of bracket 8 and near bottom edge 12. Slot 14 is` positioned on the other side of the vertical -centerof bracket 8 near top edge 11.

Means are provided to secure the syringe to bracket 8 rsecurely without distorting the barrel 2 of the syringe, thereby/interfering with accuracy and uniformity of op- .eration of the plunger. `As illustrated-these means include ablock 15 provided with a V-shaped barrel supportingV cradle 16 and a cooperating syringe clamp 17 which embraces vthe lip 3` `of the syringe and secures the t syringe tightly to the device. M. IBlock 15 has abase 1S and legs 19, 20 which are of 2,896,621 Patented J'uly 28, 1959 rice one end of block 15.

Syringe clamp 17 embraces syringe lip` 3 and secures syringe barrel 2 tightly against the V-shaped cradle 16 of block 15. The syringe clamp 17 is generally L-shaped in cross-section and is provided with a longitudinal top surface 27 and vertically extending side surfaces 248, 29. The lower Surface of clamp 17 includes a horizontallyextending portion 30, a vertically extending portion 31, and an angularly disposed portion 32 which extends from side surface 28 to portion 31. Portion 32 is disposed at an angle of approximately 45 and comprises a lip embracing surface. The remaining surfaces of syringe clamp 17 are two end walls 33, '34. Two holes 35, 36 are bored through top 27 of syringe clamp 17 to accommodate metal rods 25, 26. Screw holes 37, 38 are positioned in walls 33 and 434 to intersect respectively holes 35, 36. A knurled screw 39 is provided to fit either screw hole 37 Aor 38.

Means are provided to operate the plunger of the Vsyringe directly from a motor driven cam without the 5 of the syringe 1 and which is driven in turn from a synchronous electric motor 41. The motorI 41 is secured to the bracket 8 of the device and it transmits power to the carn 40 through a reduction gear 42. The cam 40 is secured to the out-put shaft 43 of the reduction gear by means later to be described in this speciiication.

The cam 4t) is provided with a cam surface 44 arranged in the form of a spiral. This cam surface 44 contacts directly the head y6 of the plunger y5 of the syringe, said head `6 acting as a cam follower.

Means are provided for timing the operation of the motor 41 with respect tothe rotation of the cam 40. As illustrated, these means include a springactuated switch 45 arranged in theicircuit to the motor 41 and a cam 46 driven by the out-put shaft 43 of the reduction gear 42. The cam 46 which acts as a switch actuator plate is made in the form of a circular disk and it is provided with a concentric groove 47 extending inwardly from the rear surface 48 and located near to the circumference of said cam. 'A notch 49 is positioned at a point on groove 47 so that it extends slightly outwardly toward the circumference of the actuator plate. The spring actuated switch 45, the groove 42 and the notch 49 are so arranged that power is supplied to the motor 41 when the spring actuated switch 45 is within the concentric portion of the cam groove 47 and so that the circuit to the motor is Vopened when the switch 45 is within the notch 49.

Means are provided for indicating to the operator the timing relationship between the rotation of the cam 46 and the operation of the spring actuated switch 45. As illustrated, these means comprise a circular scale 50 provided upon the front face 9 of bracket `8 and an indicia 51 arranged in the form or a dot upon the cam 46. In the preferred embodiment of this invention the ratio of the reduction gear is such thatthe output shaft 43 makes one complete revolution in 24 hours and the scale is marked in hours of operation.

Means are provided to attach Vthe cam 40 and the switch actuator plate 46 to the out-put shaft 43 of the assaeai motor and to insure their synchonous movement. In the illustrative embodiment the shaft 43 is provided with a collar 52 which is secured to the shaft 43 and is spaced from the front surface '9 of the bracket 3. The switch actuator plate 46; a thick washer 53 which serves as a spacer between switch actuator plate 46 and spiral cam 40; and cam 40 are then threaded upon the shaft 43. The foregoing elements are tightly secured together to the shaft 43 by means of a locking nut 54 which clamps the switch actuator plate 46 the washer 53 and the cam 40 between the collar 52 and the nut 54.

Clamping means 55 are affixed to the rear of motor 41 so that the device may be affixed to other apparatus.

In the specific embodiment illustrated in Figures l-4 block 15, syringe clamp 17, cam 40 and switch actuator plate 46 are made of a transparent acrylic plastic commonly sold under the trademark of Plexiglas The operation of my apparatus will be described with reference to the selected embodiment illustrated in Figures 1-4. Block 15 containing V-shaped cradle 16 is attached to bracket 8 in either slot 14 or 14, depending upon the users convenience, by means of knurled screws 24 tightened from behind rear face 10 in threaded screw holes 23. The V-shaped cradle is positioned so that the end containing metal rods 25, Z6 is nearest to shaft 43. Hypo-dermic syringe 1 containinga sample iluid is placed in V-shaped cradle 16 so that lip 3 and plunger head 6 face shaft 43. Cylindrical barrel 2 is placed in the V of V-shaped cradle 16 and lip 3 rests on the end thereof. Hypodermic syringe 1 is secured in V-shaped cradle 16 by means of syringe clamp 17 which engages metal rods 25, 26 in holes 35, 36 and slides until the angular disposed portion of the clamp leg 32 locks in place lip 3, whereupon knurled screw 39 is tightened. Plunger head 6 is positioned to contact cam 40 so that the forward motion of cam 40 is never longer than the possible movement of plunger and so that cam 410 hits the plunger head 6 and the head 6 follows the cam 40. Cam 40 is positioned on shaft 43 lso that at the beginning' of the operation of the apparatus tail portion 56 is above hypodermic syringe 1. Adjustments can bev made to align plunger 5 and cam 40 by moving syringe 1 as positioned in V-shaped cradle 16 laterally in slot 13 or 14, whichever is used, by loosening and tightening knurled screws 24 and by adjusting cam 40 by loosening and tightening locking nut 54. When syringe 1 and cam 40 have been positioned, the apparatus is turned on by turning switch `actuator plate 46. This causes spring actuatedswitch 45, which was` resting in its olf position in notch 49,

into concentric groove 47 thereby moving switch 45 to its on position and starting motor 41. By positioning notch 49 at a designated hour point on the circular scale 50 the apparatus will run for that period of time. When notch 49 reaches spring actuated switch 45, the switch 45 by virtue of attempting to relieve spring pressure will move lback into notch 49 thereby automatically stopping the apparatus.

In the selected embodiment of the apparatus illustrated in Figures 547, there is a face plate 60. Face plate 60 has a front face 61, rear face 62, top edge 63 and bottom edge 64.

Means are provided to secure to face plate 60 a spinal syringe 65 consisting of a short barrel 66 with a lip 67 at the top thereof and a long nozzle 63 thereon; a plunger 69 consisting of a long pin 70 embedded in a cylindrical top 71 which has a head consisting of a plate 72 which cooperates, with lip 67 and a knurled top 73. These means include a block 74. Block 74 has a bottom 75, top 76 and legs 77, 78. Leg 77 has an inner surface 79, outer surface 80 and top surface S1. Leg 78 has an inner surface S2, outer surface 83 and top surface 84.

Inner surface 79, inner surface 82 Vand top 76 define a groove 8S. Threaded screw holes 36 are provided in legs 77, 7S to receive screws 87 which pass from the back of plate 60 through openings 83 to secure block 74 to plate 60. A threaded screw hole 89 is positioned in the top surface 84 of leg 78 to receive a knurled screw 90. A clamp 91 cooperates with block 74.

Clamp 91 includes a top surface 92, bottom surface 93 and legs 94, 95. Leg 94 has an outer surface 96, inner surface 97, and bottom surface 98. Leg 95 has an outer surface 99, inner surface and bottom surface 101. Inner surface 97, inner surface 101 and bottom 93 define a groove 102 designed to cooperate with groove 05. A hole 103 is provided in clamp leg 94 which is positioned to be in alignment with screw hole 89 when outer surface 63 of block leg 70 is aligned in the same plane with outer surface 96 of clamp leg 94. Knurled screw 90 is provided in a sucient length to pass through hole 103 and screw into screw hole 89. Spinal syringe 65 is secured between block 7d and clamp 91 by placing barrel 66 in cooperating grooves $5 and 102 so that lip 67 is just beyond the cooperating grooves and tightening knurled screw 90. n

Means are provided to insure the controlled emission of any test fluid contained in spinal syringe 65. Said means include a reduction gear motor 104 set at a predetermined speed. lnV ythe selected embodiment illustrated in Figures 5-7 motor 104 is positioned on the rear of face plate 60 and attached to face plate 60 by means of screws 105 fastened through threaded brackets (not shown) in the motor casing and threaded holes 106 in face plate 60. A shaft 107 is connected to motor 104. T he shaft is designed to tit through an opening 103 which is provided in face plate 60 to accommodate it. Shaft 107 extends outward from the front 61 of face plate 60. r[he shaft 107 has thereon a spacer 109 positioned forward of opening 108 and reverse threading positioned at the outward end 110 of the shaft. A spiral shaped cam 111 is next positioned on shaft 107. Cam 111 has a tail end 112. Cam 111 is positioned and secured on shaft 107 by means of a locking nut 113 which screws in a counter-clockwise manner on the threaded portion of shaft 107.

A bracket 114 is aflixed to reduction gear motor 104 so that the device may be affixed to other apparatus.

In the selected embodiment of the apparatus illustrated in Figures 5-7 the block 54, clamp 91 and cam 111 are made from a transparent acrylic plastic commonly sold under the trademark of Plexiglas The operation of my apparatus will be described with reference to the selected'embodiment in Figures 5-7. Spinal syringe 65 containing a sample fluid is placed in groove 85 of block 74 so that knurled syringe plunger top 73 faces cam 111. Clamp 91 is positioned so that spinal syringe 65 is secured between groove 85 and cooperating groove 102 with lip 67 just beyond the cooperating grooves 85, 102 and knurled screw 90 is tightened. Knurled plunger top 73 vis positioned to contact cam 111 so that the forward motion :of cam 111 is never longer than the possible movement of plunger 69 and so cam 111 hits the low center of knurled syringe plunger top 73.V Cam 111 is positioned on shaft 107 so that at the beginning of the operation fof the apparatus tail 112 is above spinal syringe 65. Adjustments can be t made to align syringe plunger top 73 and cam 111 by limitations should be understood therefrom, for modifi-` cations will be obvious to those skilled in the art.

l claim: p 1 1. A motor driven syringe including a frame, a syringe comprising' a 'fbodymernber having a barrel and a lip on said barrel and a reciprocable plunger within said barrel, a bracket associated with said frame for securing said syringe to said frame, said bracket comprising a member adapted to be secured to said frame, a V-shaped cradle provided in a surface of said member and serving as a cradle for the barrel of said syringe, an adjustable clamp spaced from said member, said adjustable clampl being provided with a slanting surface and serving to embrace the lip on the body of said syringe, the axis of said slanting surface being arranged transversely with respect to the axis of said V-shaped cradle, and means for securing said clamp in a fixed position with respect to said cradle whereby the barrel of said syringe is carried by said V-shaped cradle and said clamp locks said syringe within said cradle by applying pressure to the lip of said syringe, a motor secured to said frame,

and a spiral cam driven from said motor and coacting directly with the plunger of said syringe.

2. A bracket for securing to a frame a syringe having a'barrel and a lip on said barrel, said bracket being associatedwith said frame and comprising a member adapted to be secured to said frame, a Vdshaped cradle provided in a surface of said member and serving as a cradle for the barrel of said syringe, an adjustable clamp spaced from said member, said adjustable clamp being provided with a slanting surface and serving to embrace the lip on the body of said syringe, the axis of said slanting surface being arranged transversely with respect to the axis of s'aid V-shaped cradle, and means for securing said clamp in a fixed position with respect to said cradle whereby the barrel of said syringe is carried by said V-shaped cradle and said clamp locks said syringe within said cradle by applying pressure to the lip of said syringe.

3. A sample feed device comprising a frame element having two positioned longitudinally extending elongated slots; means to secure to said frame element a hypodermic syringe having a barrel, lip, nozzle, plunger and plunger head and containing a sample uid, said means comprising a block associated with `same frame element and having a base and two legs of equal length, the inner surface of each leg dening an angle of approximately 45, said inner surfaces defining the outside edges of a V-shaped cradle, and two equal length small diameter metal rods positioned in said block; a syringe clamp which cooperates with said block and V- shaped cradle which embraces the syringe lip and secures the syringe barrel in said V-shaped cradle said syringe clamp comprising end walls, a horizontally exswitch comprising a circular switch actuator plate positioned on said shaft having on its rear surface a concentric cam groove and notch to cooperate with the activator switch; a metal spacer positioned on said shaft; a spiral shaped cam with a tail positioned on said shaft; a locking nut to engage the threaded end of said shaft and secure the actuator plate and cam on said shaft; means to clamp said device upon other apparatus.

4. A sample feed device to insure the controlled emission of a sample fluid from a syringe consisting of a frame; a block, the inner surfaces of which dene a V-shaped cradle with two small diameter equal length metal rods positioned therein; a clamp to cooperate with said block having two holes positioned therein to accommodate said metal rods; a reduction gear motor of predetermined speed and having a spring actuated switch positioned on the rear of said frame; a shaft connected to said motor and passing through said. frame; a metal spacer positioned on said shaft; a circular switch actuat-or plate positioned on said shaft having on its rear surface a concentric cam groove and switch notch to cooperate with said spring actuated switch; a metal spacer; a spiral shaped cam with a tail positioned on said shaft; a locking nut upon said shaft and securing the actuator plate and cam on said shaft; and a clamping means to secure said device upon other apparatus.

5. A sample feed device comprising a face plate; means to secure to said face plate a spinal syringe having a barrel, lip, nozzle plunger, plunger pin and plunger head and containing a sample fluid, said means comprising a block having a bottom, top, and legs, the inner surfaces of which along with the top dene a groove, and a small diameter metal rod positioned in said block; a clamp to cooperate with said block comprising a top surface, bottom surface and legs the inner surface of which along with the bottom form a groove which cooperates with said block groove, and a hole positioned in the clamp to cooperate with said metal rod; means to insure the controlled emission of the sample nid in said hypodermic syringe, said means comprising a reduction gear motor of a predetermined speed positioned on the rear of said face plate, a shaft connected to` said motor which passes through said face plate, a metal spacer positioned on said shaft; a spiral shaped cam having a tail positioned on said shaft; a locking nut to engagethe reverse threaded end of said shaft and secure the cam on said shaft; means to start and stop said apparatus; and means to clamp said device upon other apparatus.

References Cited in the le of this patent UNITED STATES PATENTS Francis et al. Aug. 15, 1933 Hinds Nov. 6, 1951 OTHER REFERENCES 

